T=int(input())
if (T>=30):
    print("Yes")
else:
    print("No") T=int(input()) T int(input()) int input() input if (T>=30):
    print("Yes")
else:
    print("No") T>=30 T 30 print("Yes") print "Yes" print("No") print "No" T=int(input()) int(input()) T
T=int(input())
if (T>=30):
    print("Yes")
else:
    print("No")